Simply put, creating individual sprites for each number is a pain and needlessly repetitive.
One solution to ease the burden on skinners would be to have osu! read a single sprite sheet of the numbers (plus period, comma, and "x"), as opposed to a separate image for each sprite. A template would have to be provided, of course, but beyond that there would be no additional work other than the making of the numbers themselves. Cropping and saving each number as a separate sprite would no longer be necessary.
Example:
Osu! would split the sheet in intervals of, for example, 55px, and separate the numbers in this fashion.
55px is an arbitrary number, by the way.
One solution to ease the burden on skinners would be to have osu! read a single sprite sheet of the numbers (plus period, comma, and "x"), as opposed to a separate image for each sprite. A template would have to be provided, of course, but beyond that there would be no additional work other than the making of the numbers themselves. Cropping and saving each number as a separate sprite would no longer be necessary.
Example:
Osu! would split the sheet in intervals of, for example, 55px, and separate the numbers in this fashion.
55px is an arbitrary number, by the way.